KR20220102290A - Tires for improving irregular wear with contact area control of each block - Google Patents

Abstract

The present invention relates to an uneven wear-improving tire through control of a contact area for each tread area. According to one embodiment of the present invention, provided is a technology improving wear resistance of a tire by reducing uneven wear occurring in a high-performance tire. The uneven wear-improving tire through the control of the contact area for each tread area according to an embodiment of the present invention comprises: a center unit, as a central portion of a tread, in which a radius from the center of the tire is uniformly formed; and a shoulder unit, as both side portions of the center unit in the tread, gradually decreasing in radius from the center of the tire in the outer direction of the tire from the center unit. A ratio of the contact area of the shoulder unit to the contact area of the tread with respect to the road surface is equal to or more than 5 % and equal to or less than 30 %.

Description

Tires with improved uneven wear by controlling the tread area by tread {TIRES FOR IMPROVING IRREGULAR WEAR WITH CONTACT AREA CONTROL OF EACH BLOCK}

The present invention relates to a tire for improving uneven wear by controlling the tread area for each tread, and more particularly, to a technology for improving the wear resistance of the tire by reducing the uneven wear phenomenon occurring in a high-performance tire.

Due to the recent commercialization of electric vehicles, the demand for tires that can be used in high-output and high-load vehicle conditions is increasing. However, the tire installed in the vehicle of high output and high load as described above has a problem in that abrasion resistance performance is adversely applied.

In addition, a separate high-performance tire is used for a high-performance vehicle such as an electric vehicle, and the high-performance tire has a round type in which the tire is grounded on the road surface, which may be disadvantageous in wear resistance performance.

In the prior art, the specific gravity of the groove relative to the total area for each part was derived as a factor based on the pattern shape of the two-dimensional tread. Through this, the tendency of uneven wear (early wear on the center part or early wear on the shoulder part) was analyzed, but various tire design factors were not considered due to the two-dimensional limit. This is because there may be a difference in the degree of influence between a tire having a square type tire and a round type tire having a ground shape of the tire.

In Korean Patent Registration No. 10-1999-0000214 (Title of the Invention: Tread of a tire with excellent wear resistance), in composing the tread of the tire, NG% of the shoulder part constituting the pattern of the tread / NG% of the center part Disclosed is a tread of a tire, characterized in that it is formed to be in the range of 1.00 to 1.40.

Republic of Korea Patent Registration No. 10-1999-0000214

SUMMARY OF THE INVENTION An object of the present invention to solve the above problems is to improve the wear resistance of the tire by reducing the uneven wear phenomenon occurring in the high-performance tire.

The technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those of ordinary skill in the art to which the present invention belongs from the description below. There will be.

According to an aspect of the present invention, there is provided a tire including a tread, comprising: a center portion having a constant radius from the center of the tire as a central portion of the tread; and shoulder portions in which the radius from the center of the tire gradually decreases from the center portion to the outer direction of the tire from the center portion on both sides of the center portion in the tread. The ratio of the contact area of the shoulder portion is characterized in that 5% or more and less than 30%.

In an embodiment of the present invention, the roundness of the ground shape of the tread may be 40 or more and less than 80.

In an embodiment of the present invention, the contour of the ground shape of the tread may have a curved line.

In an embodiment of the present invention, the contact area of the tread may be a contact area between the tread and the road surface while the tire is running.

In an embodiment of the present invention, the difference between the wear amount (%) of the center part and the wear amount (%) of the shoulder part may be 0 to 10%.

The effect of the present invention according to the above configuration is to control the tangential speed of each part by adjusting the contact area of the center part and the shoulder part of the tread, thereby reducing the difference in the amount of wear between the center part and the shoulder part, thereby reducing uneven wear This means that the wear resistance of the tire can be improved.

The effects of the present invention are not limited to the above effects, and it should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a perspective view of a portion of a tire according to an embodiment of the present invention.
2 is an image of a ground shape of a tire according to an embodiment of the present invention.
3 is a graph of the speed for each design factor according to an embodiment of the present invention.
4 and 5 are images of a ground shape of each tire.
6 to 8 are graphs for analyzing the wear amount of the tire according to each embodiment.

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be embodied in several different forms, and thus is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part is "connected (connected, contacted, coupled)" with another part, it is not only "directly connected" but also "indirectly connected" with another member interposed therebetween. "Including cases where In addition, when a part "includes" a certain component, this means that other components may be further provided without excluding other components unless otherwise stated.

The terms used herein are used only to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present specification, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that this does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of a portion of a tire according to an embodiment of the present invention, and FIG. 2 is an image of a grounding shape of a tire according to an embodiment of the present invention. In FIG. 1, No. 1 may indicate a center portion and No. 2 may indicate a shoulder portion.

1 and 2 , the tire of the present invention including a tread includes a center portion having a constant radius from the center of the tire as a center portion of the tread; and shoulder portions in which the radius from the center of the tire gradually decreases from the center portion to the outer direction of the tire from the center portion as side portions of the center portion in the tread.

Here, the tread contact area may be a contact area between the tread and the road surface while the tire is running. Similarly, the contact area of the center part may be a contact area between the center part and the road surface while the tire is running, and the contact area of the shoulder part may be a contact area between the shoulder part and the road surface while the tire is running.

In addition, the ground shape of the tire of the present invention may be a round type. The round type means that the contour of the ground shape of the tread may have a curved line.

Since the ground shape of the tire of the present invention is a round type as described above, there is a problem in that the difference in the amount of wear of the center part and the shoulder part increases during driving of the present invention, and the present invention may have been devised to solve this problem. .

At the time of rolling of the tire, in the tread surface with respect to the road surface, since the turning radius of the center of the center part and the turning radius of the center of the shoulder part are different from each other, the tangential speed ( V1) and the tangential velocity V2 with respect to the road surface at the center of the shoulder portion may be different.

As described above, since the respective tangential velocities are different, slip may occur in the center portion during tire driving, and wear of the center portion is more accelerated than the shoulder portion due to this phenomenon, so the tangential speed V1 of the center portion and Reducing the difference in the tangential velocity V2 of the shoulder portion may be advantageous in improving the wear performance of the tire.

3 is a graph of a speed for each design factor according to an embodiment of the present invention. In FIG. 3 , the vertical axis may indicate tangential velocity, and the horizontal axis may indicate each design factor. Here, center is the tangential velocity of the center part and shoulder is the tangential velocity of the shoulder part.

In addition, the equilibrium speed 1 is the tangential speed of the center part when the tangential speed of the center part and the tangential velocity of the shoulder part are in equilibrium when the tire land/sea ratio of the present invention is controlled as in the embodiment of the present invention and the tangential velocity of the center part and the tangential velocity of the shoulder part are balanced. and the average value of the tangential velocity of the shoulder portion. At this time, the equilibrium velocity 1 may be Va1.

And, the equilibrium speed 2 is the tangential direction of the center when the tangential speed of the center part and the tangential speed of the shoulder part are balanced when the tire is running without controlling the tire land/sea ratio of the present invention as in the embodiment of the present invention. It may be an average value of the velocity and the tangential velocity of the shoulder. At this time, the equilibrium velocity 1 may be Va2.

In the above, the Land/Sea Ratio is the ratio of the area where a groove such as a groove is formed in the tread and the area other than that. Hereinafter, it is the same.

As shown in FIG. 3 , there may be an equilibrium section between the tangential velocity of the center portion and the shoulder portion. In addition, the section in which the tire is balanced as described above can be changed when the tire is driven by the difference between the center portion's adhesion force and the shoulder portion's grip force. Here, the section may be a predetermined speed section during tire driving.

However, since the adhesion force is due to the contact area due to the characteristics of the rubber forming the tire, the difference between the center part's adhesion force and the shoulder part's traction force is realized by adjusting the center part's contact area and the shoulder's contact area. can be That is, by adjusting the Land/Sea Ratio of the center part or the shoulder part, the difference between the center part's adhesion force and the shoulder part's traction force can be realized. , it is possible to improve the wear resistance performance of the tire of the present invention.

In order to implement the above effect, the ratio of the tread area of the shoulder portion to the tread area of the tread on the road surface may be 5% or more and less than 30%. Here, when the ratio of the tread area of the shoulder to the tread area is less than 5%, the tread shape of the tire of the present invention is not formed in a round type, so that the handling performance of the tire of the present invention may decrease. . In addition, when the ratio of the tread area of the shoulder to the tread area of the tread is 30% or more, the difference between the tangential speed of the center and the tangential speed of the shoulder increases as described above, so that the tendency of early wear of the center increases. The wear resistance performance of the tire may be reduced.

The roundness of the ground shape of the tread is 40 or more and less than 80, and the roundness can be calculated by the following [Equation].

[Equation]

Roundness = A _T /(W _max XL _max ) X100

where A _T is the tread area of the tread, W _max is the maximum width in the tread shape of the tread, and L _max is the maximum length in the tread shape of the tread.

If the roundness is less than 40, the roundness is too small and the performance such as handling of the tire is improved, but a phenomenon that early wear of the center part is deepened may occur. In addition, when the roundness is 80 or more, the wear difference between the center portion and the shoulder portion is small due to the characteristics of the tire, so that the need for controlling the contact area between the center portion and the shoulder portion as described above may be reduced.

When the tire design as described above is performed, the difference between the wear amount (%) of the center part and the wear amount (%) of the shoulder part may be 0 to 10%. Accordingly, uneven abrasion of the tire of the present invention may be reduced, and the wear resistance performance of the tire of the present invention may be improved.

4 and 5 are images of a ground shape of each tire. In each of (a), (b) and (c) of FIG. 4 , the contact area of the center part and the shoulder part is adjusted, respectively, as in the tire of the present invention, the tires 1-1 to 3-1 are shown. An image of a ground shape is disclosed.

And, in each of (a), (b) (c) of FIG. 5 , the first to second tires to which the contact area adjustment for the center part and the shoulder part is not performed as in the tire of the present invention described above. An image of the tread shape of a tire is disclosed.

In the analysis of the ratio of the tread area of the shoulder to the tread area, the corresponding ratio was measured to be 28.4% in the 1-1 tire, the corresponding ratio was measured to be 28.9% in the 2-1 tire, and the 3-1 tire was measured to be 27.8%.

And, the corresponding ratio was measured to be 33.7% in the 1-2 tire, 37.2% in the 2-2 tire, and 45.6% in the 3-2 tire.

Here, the same weight was provided to each tire, and the ground shape and area for each tire were analyzed when each tire rotates. And, the 1-1 tire and the 1-2 tire are the same tires except whether the tread pattern is adjusted or not, and the 2-1 tire and the 2-2 tire are the same tires except for whether the tread pattern is adjusted or not, Tires 3-1 and 3-2 differ only in whether the tread pattern is adjusted and the rest are the same tires.

And, FIGS. 6 to 8 are graphs for analyzing the wear amount of the tire according to each embodiment. In each of the graphs of FIGS. 6 to 8 , the vertical axis is for the groove depth (mm) of the tread, and the horizontal axis is for the position of each groove of the tread. Specifically, each position of Out sho. (Out shoulder), 1G, 2G, 3G, 4G, and in sho. (In shoulder) on the tread along the direction of the rotation axis of the tire can be determined, and at each position by the longitudinal axis may indicate the change in the groove depth of the tread.

The graph of FIG. 6 (a) shows the groove depth at each position on the tread according to each driving distance when the 1-1 tire is rotated, a graph is a graph when the driving distance is 0Km, and b graph is a graph for a mileage of 5,000 km, and graph c is a graph for a mileage of 10,000 km.

And, the graph of FIG. 6 (b) shows the depth of the groove at each position on the tread according to each driving distance when the first and second tires are rotated, and the graph a is a graph when the driving distance is 0Km, Graph b is a graph for a mileage of 5,000 km, and graph c is a graph for a mileage of 10,000 km.

7(a) graph shows the groove depth at each position on the tread according to each driving distance when the 2-1 tire is rotated, a graph is a graph when the driving distance is 0Km, b graph is a graph for a mileage of 5,277Km, and graph c is a graph for a mileage of 10,076Km.

And, the graph of FIG. 7 (b) shows the depth of the groove at each position on the tread according to each driving distance when the 2-2 tire is rotated, and the graph a is a graph when the driving distance is 0Km, Graph b is a graph with a driving distance of 5,277Km, and graph c is a graph with a driving distance of 10,076Km.

The graph of FIG. 8 (a) shows the depth of the groove at each position on the tread according to each driving distance when the 3-1 tire is rotated, a graph is a graph in the case of a driving distance of 0Km, and a graph b is a graph for a mileage of 5,000 km, graph c is a graph for a mileage of 10,000 km, graph d is a graph for a mileage of 15,000 km, and graph e is a graph for a mileage of 20,000 km.

The graph of FIG. 8 (b) shows the groove depth at each position on the tread according to each driving distance when the 3-2 tire is rotated. is a graph for a mileage of 5,000 km, graph c is a graph for a mileage of 10,000 km, graph d is a graph for a mileage of 15,000 km, and graph e is a graph for a mileage of 20,000 km.

In the above rotation, the wear difference, which is the difference in the wear amount of the center part and the shoulder part (the wear amount of the center part (%) - the wear amount of the shoulder part (%)) in the 1-1 tire, is 0%, and the wear difference in the 1-2 tire is -8%.

In addition, the difference in the amount of wear in the 2-1 tire is -3%, and the difference in the amount of wear in the tire 2-2 is -11%.

And, the difference in the amount of wear in the 3-1 tire is -5%, and the difference in the amount of wear in the 3-2 tire is -12%.

As can be seen from the numerical descriptions related to FIGS. 6 to 8 and each drawing, the tread area of the shoulder portion compared to the tread area of the tread like the 1-1 tire, the 2-1 tire, and the 3-1 tire is In a tire having a ratio of less than 30%, a difference in the amount of wear between the center portion and the shoulder portion is formed to be less than 10%, and it can be seen that uneven wear is reduced.

The above description of the present invention is for illustration, and those of ordinary skill in the art to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and likewise components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention.

C: center part
S: shoulder

Claims (5)

A tire comprising a tread, comprising:
a center portion having a constant radius from the center of the tire as a central portion of the tread; and
In the tread, shoulder portions are located on both sides of the center portion, and the radius from the center of the tire gradually decreases from the center portion to the outer direction of the tire.
The tire for improving uneven wear by controlling the tread area for each tread, characterized in that the ratio of the tread area of the shoulder portion to the tread area of the tread with respect to the road surface is 5% or more and less than 30%.
The method according to claim 1,
The flatness of the tread of the ground shape of the tread is 40 or more and less than 80, and the roundness is calculated by the following equation.
Roundness = A _T /(W _max XL _max )X100
Here, A _T is the tread area of the tread, W _max is the maximum width in the tread shape of the tread, and L _max is the maximum length in the tread shape of the tread.
The method according to claim 1,
The tire for improving uneven wear by controlling the tread area for each tread, characterized in that the contour of the tread of the tread has a curved line.
The method according to claim 1,
The tire for improving uneven wear by controlling the tread area for each tread, characterized in that the tread area is a contact area between the tread and the road surface while the tire is running.
The method according to claim 1,
The tire for improving uneven wear through the tread area control for each tread, characterized in that the difference between the wear amount (%) of the center part and the wear amount (%) of the shoulder part is 0 to 10%.

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